Behind Closed Doors
by TabbyCat33098
Summary: Mary walks in on Sherlock and John having sex a total of six times. It doesn't take her that long to join them. Mary/Sherlock/John OT3 PWP.


A/N: It appears that I have OT3'd. I'm not entirely sure how, tbh, only that its a thing that happened. This was partially inspired by the song I Write Sins Not Tragedies, by Panic! At The Disco, since I got to thinking, what would happen if Mary was a whore because she had sex with John and Sherlock before the wedding? Or John was a whore because he cheated on Mary with Sherlock before the wedding? Instead, everyone had sex with everyone else, and this became full blown PWP.

I am truly very sorry for not focusing on my fics. That'll happen soon, I promise, just not tonight. Instead, tonight, I'm gonna beg for reviews, please. Just a few short words describing your thoughts would be nice, lol. Anyways, thanks for clicking on this work, and happy reading! :)

* * *

**Behind Closed Doors**

The first time she walks in on them, she stares at them in horror and vague interest, watching as Sherlock's hips undulate steadily behind John, who's on his knees on the bed, and pleasured noises force their way through John's lips. John's eyes are closed, thank God, and so are Sherlock's, when Mary glances at him. For some reason, Mary feels paralyzed, her feet rooted to the ground, forcing her to see the act through to the end.

Sherlock is still pounding forcefully into John. His hands grip John's hips, and Mary thinks she can see faint bruises forming where Sherlock's fingers touch John's skin. A light sheen of sweat glazes them both. Harsh pants escape from their mouths, punctuated by breathy sighs and sharp moans. As Mary watches, Sherlock's hips begin to stutter. He pulses forward suddenly, dropping forward over John's back, and a low groan slips from his mouth. A moment later, and with a shout, John stiffens before collapsing to the bed. There's only one logical explanation as to what could have occurred.

To her surprise, Mary doesn't feel disgust. She doesn't feel anger that her fiancee is having sex with someone who isn't her. She doesn't feel jealousy that John finds Sherlock more sexually satisfying than her.

No, what Mary feels is arousal. Fire-hot, all-consuming, almost painful arousal.

As Sherlock rolls off of John, his eyes open and come into contact with Mary's. Sherlock freezes, and the two engage in a stare-down. Sherlock opens his mouth to say something.

Without a word, Mary flees.

* * *

The second time she walks in on them, she knows immediately it must have been a calculated measure on Sherlock's part, though not John's. There's no other explanation for the sight she sees before her eyes.

John is riding Sherlock on the couch, his back to Mary. His entire body seems to move with each roll and thrust, the movement flowing through his shoulders and back until his entire being is focused on this one act. Sherlock's legs are spread easily on the couch, with one hooked on to the back of the couch and one resting on the floor. His hands rest on John's thighs, but he remains perfectly still apart from a few shudders rolling through his body from time to time.

From where Mary stands, she has a perfect view of not only the main action, but also of every expression on Sherlock's face. He's biting his lower lip, presumably to stifle his moans, and God help Mary if it isn't one of the hottest things she's ever seen. His head is thrown back in pleasure, exposing his neck to both John and Mary, and as Mary watches, John leans forward to nip and lick at it. He stops at Sherlock's collarbone and remains there for a moment, where small noises and wet slurps indicate that he's marking Sherlock as his own. He moves back up to kiss Sherlock square on the mouth, leaving behind a hickey that confirms Mary's suspicions.

"Sherlock," John groans. "Sherlock, I'm so close." He sits back up and picks up the pace. One of his hands reaches down to his cock, though it's hidden from Mary's view.

Sherlock opens his eyes and tilts his head forward until he can look into John's eyes. "Then come," he commands, in that deep voice that leaves Mary weak in the knees.

John obeys. Within a minute, he's screaming Sherlock's name and coming. Sherlock comes as well, with a tense groan and an arched back, and afterwards, they both relax into each other. As John snuggles into Sherlock's chest, Sherlock stares directly at Mary, a challenge written in his eyes.

With a small squeak and burning cheeks, Mary drops the groceries she's been holding the whole time and runs out of the flat.

"Mary?" calls a familiar voice in confusion, but she doesn't listen.

* * *

The third time she walks in on them, there is no doubt in her mind that they engineered this particular scenario to snare her in. There's no other reason for them to be fucking on her bed.

This time it's John who's topping. Sherlock's been thrown on his back with John covering him, dominating him. Sherlock's slender arms reach up behind him to grip the headboard, and his incredibly long legs stretch out behind John, feet flexed and toes pointed. John's arms have looped below Sherlock's arms and clutch at Sherlock's shoulders. His forehead is touching Sherlock's, both of them gazing into each other's eyes, seemingly without a care for the rest of the world.

The sex itself appears to be slow, more like it is when he fucks Mary herself, and Mary can't help but put herself in Sherlock's position. She knows firsthand how unique and loved John makes her feel in this position, to the point where it's not so much "fucking" as it is "making love." There's no doubt as to why Sherlock's entire body is flushed pink in the wake of John's careful ministrations. And still, Mary has yet to feel a single negative emotion about John using Sherlock to take her position, or even any emotion other than extreme arousal and full blown lust.

"Oh my," she whispers, but it's enough to catch both John and Sherlock's attentions. Though neither of them stop moving, they both look over at her with inviting grins plastered on their faces. Sherlock releases the bedframe with one hand to form a _come hither_ gesture. Mary finds her vision focusing on nothing but Sherlock's impossibly long fingers. _They would be perfect for fingering_, she thinks, unbidden.

Before she knows what she's doing, Mary has closed the door behind her and starts unbuttoning her shirt. Her shirt falls off somewhere between the door and the bed, and her skirt and bra follow a mere few footsteps later. Her underwear is flung off into some far corner of the room once she collapses onto the bed, and she loses all rational thought for the next hour or so.

* * *

The fourth time she walks in on them, she's just gotten up to go to the restroom in the morning after a glorious night of mind blowing sex. She still feels a little stretched out from last night's activities, and a light blanket of contentment cloaks her body. She quickly washes up a bit, washing the semen off her stomach and thighs, before returning to the bedroom.

When she opens the door again, she sees John lounging leisurely on the bed, his arms crossed behind his head. He smiles lazily at her, but she's distracted by something.

"Where's Sherlock?" she asks. John's grin turns a little sly, but before he can answer, she figures it out herself. There's a rather telltale bulge moving about under the covers in small patterns that are nonetheless easily recognizable, right about where John's cock would be. "You bastard!" Mary exclaims in mock indignation. "That's _my _cock, you arse! Get your own fiancee!" She pulls the covers off the bed, ignoring John's easy laugh, pushes Sherlock away, and takes over right where he left off.

Sherlock chuckles as well. "Possessive, are we?" he whispers into her ear. His body wraps around her own, his warmth covering hers, and she can feel him filling against her arse. A rush of heat fills her body, and she moans around the cock in her mouth. John groans in response, and Sherlock just chuckles again. "We can't have that. I do so love to share," he all but purrs. The warmth disappears briefly, but it reappears again as his mouth relocates to another, more sensitive area between Mary's thighs. She moans again around John's cock, and that's what seems to do it, because a moment later, she nearly chokes on John's cum. But she's had practice with this, so she swallows it all down, just in time to cry out a minute later as Sherlock takes her to orgasm as well.

* * *

The fifth time she walks in on them, they're cuddling together on the couch, naked and with a musky scent lingering in the air that can only be attributed to one activity.

Mary shakes her head in disappointment as she hangs up her coat. "What have I told you about fucking without me?" she says threateningly. Sherlock and John look at each other with poorly disguised excitement and smugness. That's when Mary knows she's been played, but she can't back down now. Besides, this gives her a chance to punish them more thoroughly, all under the guise of having been disobeyed.

"That you'll punish us," John replies dutifully in answer to her question. Sherlock nods along in agreement.

Mary smirks. "You seem almost too excited about your punishment," she muses as she stalks towards them, although she makes a quick stop by a chest sitting in the corner, covered haphazardly with columns of paper and books. They teeter as she opens the door on the side and reaches in to grab a few toys. "I'm starting to think you look forward to it. That you deliberately disobey me to receive it," she continues, letting them know she's caught on to their scheme without saying it outright. By the soft _damn!_ that John mutters, she knows she's hit the nail on the head.

Still. It doesn't mean she can't have a little fun.

"Would you like to tell me which one of you started it?" Mary whispers menacingly as she stands up, smacking a riding crop against her left hand. She notices the small byplay that transpires between John and Sherlock (a raised eyebrow, a subtle nod), and though she smirks again, she doesn't comment.

"I did," John volunteers.

Mary raises an eyebrow and begins walking towards them. "I did what, John?"

John swallows, though whether in excitement or fear, Mary can't tell. "I did, mistress."

Mary grins. "That's better," she coos as she reaches them. With a swift motion, she pulls the handcuffs from her pocket and cuffs John's hands together. "Hold them above his head and don't move," she barks at Sherlock, before returning her attention to John. She trails the riding crop down his chest and stomach, watching the sensitive skin quiver under her touch. "Then we'll have to punish you first, won't we?" she whispers, still grinning.

* * *

The sixth time she walks in on them, she's wearing her wedding dress, and John and Sherlock are both in tuxes. She's just finished locking the door and calling down to room service and telling them not to disturb her or her guests for the next 24 hours at the very least. She moves from the small front room into the adjoining bedroom, only to be greeted by the sight of two very dapper gentlemen kissing passionately against the wall. John's got Sherlock pressed up against it this time, using his superior strength to his advantage, though Sherlock doesn't appear to be fighting very hard.

"Naughty boys," Mary reprimands them, walking forward. "This is _my_ wedding night, after all."

John breaks away from Sherlock. Both of them are breathing heavily, but it doesn't stop Mary's husband from laughing and saying, "It's my wedding night, too, love."

Mary grins in response. "So it only makes sense that we enjoy it together first, doesn't it?" she suggests, staring pointedly at Sherlock.

But Sherlock refuses to be intimidated. "That doesn't mean we can't all enjoy it together," he argues, though there's an amused twinkle in his eye that says he knows she's only kidding, and he's about to call her out on it. Sure enough, a moment later, Sherlock's lips are pressed in a crushing kiss against Mary's lips, while John proceeds in making short work of her intricate wedding dress. Within minutes, Mary's been pushed to the bed and is writhing helplessly under the attentive ministrations of John and Sherlock.

"You wouldn't deny this, would you?" Sherlock whispers to her, and she nearly climaxes at the very sound of his voice. He knows her weakness, and he's exploiting it to it's full measure, she knows. But despite herself, she can't quite begrudge him the trickery when the results are so pleasurable.

"No," she gasps out. "Of course not." And Sherlock and John both laugh before returning their attentions to her body. Suddenly, there is a burning fire everywhere on her skin, trailing down her arms while also engulfing her calves, sucking in her fingers while simultaneously managing to penetrate her. She can no longer see anything but the sharp red of arousal, nor hear anything but the rush of blood pumping through her veins, nor feel anything but Sherlock's languid, assured strokes and John's hands and mouth and tongue on her _everywhere_. She comes in a rush of heat and ecstasy, her entire world going white and hazy.

When she finally comes down from the high, she sees that Sherlock and John have gotten each other naked and are well on their way to rutting their way to orgasm. That, of course, is _far _too an undignified way to climax, Mary decides, especially since she wants to feel John inside her as well before he comes, and so she pushes her way between them and takes each of them in her hands.

"Don't worry," she whispers, in response to John's saddened whimper. "We've got the rest of our lives for this."

**FIN**


End file.
